August 1997

Effect of Timolol on the Diurnal Intraocular Pressure in Exfoliation and Primary Open-angle Glaucoma

Author Affiliations

From the University Department of Ophthalmology, AHEPA Hospital, Thessaloníki, Greece (Drs Konstas and Mantziris), the Pharmaceutical Research Corporation, Charleston, SC (Ms Cate and Dr Stewart), and the Carolina Eye Institute at the University of South Carolina, Columbia (Dr Stewart).

Arch Ophthalmol. 1997;115(8):975-979. doi:10.1001/archopht.1997.01100160145002

Objective:  To describe and compare the diurnal intraocular pressure (IOP) variation in patients with exfoliation glaucoma (EXG) and primary open-angle glaucoma (POAG) who were treated with a solution of timolol maleate (0.5%) twice daily.

Design:  Consecutive Greek patients who were newly diagnosed as having EXG or POAG were prospectively investigated; they underwent 24-hour diurnal IOP measurements first without therapy and then 6 months afterward while they were being treated with timolol maleate (0.5%). After matching for age, 38 pairs of patients with these 2 types of glaucoma were compared.

Results:  Untreated patients with EXG had significantly higher IOP values for all time points assessed and a greater mean range of IOPs (11.8 mm Hg for EXG vs 7.6 mm Hg for POAG; P≤.001 ). Following therapy with timolol maleate (0.5%) given twice daily, patients with EXG had higher IOP values for the measurements that were obtained at 6 and 10 am, 10 pm, and 2 am, a higher mean range of IOPs (7.0 mm Hg for EXG vs 5.6 mm Hg for POAG; P=.03), and a higher maximum IOP (mean, 24.9 mm Hg for EXG vs 20.9 mm Hg for POAG; P=.003). The reduction of the range of diurnal variation of IOP was more pronounced in patients with EXG than in patients with POAG (40% vs 26%; P=.04). Twenty-two (58%) of 38 patients with EXG and 20 (53%) of 38 patients with POAG had peak IOP values that were found outside office hours. Only 5 (13%) of the patients with EXG exhibited an IOP of 18 mm Hg or less at all time points compared with 12 (32%) of the patients with POAG (P=.05).

Conclusion:  Despite a greater initial IOP reduction in the patients with EXG treated with timolol, a higher IOP and significant fluctuation in the diurnal curve of IOP during the time in which patients received therapy still characterized EXG from POAG.